A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
If you hold farts in during the day, they'll just come out when you sleep.
16
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
You forget 90% of your dreams.
256
Honeybees never sleep.
276
You burn more calories sleeping than you do watching television.
348
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Cows can sleep standing up, but they can only dream lying down.
745